Process of producing isoprene.



' 400-600 (3., at pressures less than 60 milli on ems PATENT ()FFICE. a

vLUCAS PETRON IKYBIA KIDES AND RIGfi'ABD BLAIR EABLE, O]? BOSTON, MASSACHU- SETTS, 'ABSIG-NORS TO HOOD RUBBER COMPANY; OF BOSTON, MASSACHUSETTS, A

CORPORATION -01B MASSQOHUSETTS.

1,094,222. No Drawing.

rnoenss or Paonucme' Isornrmn.

i sp ifi ati n r Lettersl'atent. Patented 21, 1914.

To all whom it mag/0mm KIDES and Riemann B. Earns, citizens of the United States, residing at Boston, -Massachusetts, have invented certain new and use-. ful Improvements in Processes ofProducing- Isoprene, of which the following is a specifi cation. P

Our invention relates to a new and valuable process for producing isoprene (2- methylbutadiene 1.3 B methyldivinyl) which is a valuable hydrocarbon useful in the preparation of rubber or terpenes.

The new process consists in passing the vapors of isoamylene oxid of the formula:

I cH -e-cur-on.

over heated dehydrating catalytics suchas aluminum silicate at temperatures from meters of mercury.

In order to illustrate the new process more fully, the following example is given: Isoamylene oxid is distilled .slowl over alu I minum silicate, either powdere -or.in briquet form, which is kept at the temperature of 450 C. and the pressure of one m llimeter -of mercury by a vacuum pump. The prodnets of the reactionare condensed in sultable receivers by means of refrigerating agents and purified by fractional distillation. The fract-Ion boiling at 32-37 0., consists of nearly pure isoprene and may be used in this state of purit The other products of the reaction are igh boiling roducts of unknown nature, valeraldehy e and traces of trimethylethelene. The yield of isoprene,

containing only traces of trimethylet-hylene,

is over 70% of the thieory. The formation of isoprene takes place by the splitting off of -water according to the equation:

The process is useful at the ordinary pressure but the yield of isoprene is largelyincreased by carrying out the operation in a in vazmoat Application and November 11,1911.- ..Seria1 no. 659,828.

p 2. process for producing isoprene, which Be it known that we, 'LuoAs P. KYRIA- "comprises passing the 1 vapors of an 1s0- amylene oxid over heated aluminum silicate.

4. A process for producing isoprene which comprises passing the vapors of. an isoamylene oxid over heated aluminum silicate at less than atmospheric pressure.

5. A process forproducing isoprene which comprlses amylene oxld over a dehydrating catalytic at a temperature between 400 and 600 0.

6. process for producing isoprene which com rises passing the vapors of an isoamy efie OXld over a dehydrating catalytic at a temperature between 400 and 600 C. pressures less than millimeters of mercury. v 7. process for producing isoprene which OOIIIPI'ISGS: passing the vapors .of I an isoamylene oxld over an aluminum silicate at a temperature lpet-ween' iOO and 600? C. in cam/,0 at pressures less than 60 millimeters of mercury.

8. The '--process for' producing isoprene which consists. in passing the vapors of iso "'amylene oxid of the formula overheated dehydrating catalytics at temperatures from 400+600 (3., im, owcuo, at pressures less than 60 millimeters of mercury. Q

9. The process for producing iso rene which consists in passing the vapors o isoamylene oxid of the formula: 1

' over aluminum silicate at temperatures from 400-600 C., in 'vacuo, at pressures less than 60 millimeters of mercur testimony whereof, we aifix our signatures inresence of two witnesses. LU AS PETRON KYRIAKIDES.

' RIGHARDBLAIR EARLE. Witnesses:

" Jnssm R. Mo'rr, M. Amen HAGARTY.

assing the vapors. of an 1s0- 

